Turbine-vane.



No. 853,334. PATENTED MAY 14, 1907.

' c. A. BAGKSTROM'.

TURBINE VANB.

APPLICATION FILED 001'. 24.1904.

1' 6 INVENTOR ATTORNEY! WIINESS5= 6 i UN TED sTA Es PATENT OFFICE.

- CHARLES A. BACKSTROM, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO BACK- lineof the series.

' for casting, the interior portion of the vane beportion of a runningwheel with the vanes in STROMSMITH STEAM TURBINE & PORATION WISCONSIN.

MANUFACTURING COMPANY, A COR- TURBINE-VANE- Specification of LettersPatent.

Patented May 14, 1907.

Be it known that I, CHARLES A. BACK- sTRoM, a citizen of the UnitedStates, residing at Milwaukee, county of Milwaukee, and State ofWisconsin, have invented new and useful Improvements in Turbine-Vanes,of which the following is a specification.

My invention relates to improvements in I turbine vanes.

The objects of my invention are to secure absolute uniformity andaccuracy in the contour of the vanes as well as in their position in therunning wheel, and to avoid the necessity of finishing and she ing thesurfaces of the vanes by machine tools. Also to providefor casting thevanes in a set or series of connected vanes which may be unitedlysecured in position in the running wheel, thus avoiding-the labor ofassembling the vanes separately and dis ensing with numerous rivets.

A further 0 ject of my invention is to pro.- vide the vanes withexterior shells of smoother and harder material than that ordinarilyused To all, whom it may concern: I

mg composed of softer material which, however,is integrally united tothe hard outer shell. In the following descri tion reference, is had tothe accompanying awings in which Figure 1 is a View 'of a series ofvanes ready for insertion in a running wheel. Fig. 2 is a peripheralview of the same with two of the vanes partially broken away along thecenter Fig. 3 is a transverse sectional view drawn on line XX of Fig. 1.Fig. 4 is an end view of one of the shells showing the edges of thecurved walls. Fig. 5 is a similar view showing a modified form ofconstruction. Fig. 6 is a view of the concave side of a shell such as isshown in Fig. 5. Fig. 7 is a plan view of a portion of the mold, withthe cope partially broken away to show the upper ends of shells similarto those shown in igs. 5 and 6. Fig. 8 is a vertical sectional view ofthe mold, drawn transversely to a row of shells. Fig. 9 is a sectionalview of a position.

Like parts are identified by the same reference characters throughoutthe several views. The drawings are illustrations of the construction ofvanes designed for use in an impulse turbine arranged for inward-radialattack, and the vanes 1 are to be mounted between disks 2 whichconstitute the sides of a running wheel as shown in Fig. 8. Inconstructing these vanes, a series of shells are formed, preferably bystamping them from sheet metal, such as nickel-steel, and each shell, inthe construction shown, is rovided I with an end wall 3 and two curvewalls 4 and 5, the inner faces of which constitute finished concave andconvex surfaces of the bucket .cavities when the vanes are com-' pleted.The walls 4 and 5 may, if desired, be extended in the form of wings 6and 7 on each side and the space between these wings, if used, and thewalls 4 and 5, is filled with a core of molding sand or other suitablematerial. A mold is then prepared, having a curved channel in which theshells are placed in a row with the walls 4 of one shell abutting thewalls 5 of the next at the side edges and with open cavities 11 betweenthe divergent central portions of these walls. The space between thewalls 4 and 5 of each shell constitutes a bucket cavity in the com letedseries of vanes and in the mold. Tliis cavity is covered by the wall 3.The cope is then prepared with a channel 10, corres onding ln'positionwith the row of shells, an molten metal is then flowed into this channel10 to fill it, and the cavities'll between theshells,

under conditions of temperature to cause it to fuse with the shellsurfaces with which it contacts. On removing the casting with the shellsthus integrally connected, the vanes are completed by merel trimming offthe edges, or thawings 6 an 7 if such wings are employed. The walls 4and 5 of each shell form the concave wall of one vane and the convexwall of the-next succeeding vane.

. The object of the wings 6 and 7 is to keep the molten metal fromentering the bucket cavities where the cores are imperfect, but if themolds and cores are carefully prepared, the wings may be dispensed withand the work of trimming the edges of the vanes lar ely if not entirelyavoided.

l the vanes thus produced in a single casting operation. are inte rallyconnected and held in position by the in of cast metal which filled thechannel 10 in the mold, and

this bar ma be "formed to fit a channel 15 in one of the isks 2 of therunning wheel, thus accurately determining the position of the vanes andfacilitating their attachment to the disks.

It will be understood that while I have shown and described theinvention with reference to a s ecia'l form of turbine, it may beadapted to t e'requirements of any style of turbine, and, if desired,the connecting bars may be'formed at both ends of the vanes, or

the vanes may be separately formed, or connected in series, having anydesired number.

-By stamping the surface walls of the vanes from sheet metal, absoluteuniformity and accuracy 1s insured in any case, and the vanes arerovided With smooth hard surfaces who require no finishing.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is,r

' 1.. A turbine vane having a stamped exterior surface of relativelyhard material and a filling of cast metal between the surface walls, 1

2. A cast metal turbine vane provided 3. A series of turbine vanesintegrally surface of stamped metal fused to the cast metal interior.

ing-bar, each vane being surfaced with metal of a diiferent characterfrom that composin the bar, and connected with the bar througprojections on the latter extending between the surface walls.

5. A series of turbine vanes havin body portions of cast-metal formedintegrally with a curved metallic eonnectin bar and having surfaces ofdifferent materia froni that composing the bodyortions. r

in the presence of two witnesses.

CHARLES A'. BACKSTROM.

Witnesses: I

JAB. B. ERWIN, LEVERETT 0. WHEELER.

, 45 In testimonyw ereof I' aflix'my signature

